[tlbuild] asy and other status

[Karl Berry]

TL build folk,

First, I've committed asymptote 2.21 sources.  Bowman is working on
another release, but expects changes to be small.  I will not be
updating the runtime until after the freeze, so it won't run, but I
figured we could at least try compilations.  (It worked for me.)  So
feel free to give that compile a shot now if you wish.

Second, I've committed various other fixes that have been bandied about,
details can be seen in the log.  I believe all the test failures that
have been reported have been ameliorated now.  It would be good to rerun
a full build to make sure that nothing new, or old, is failing.

Third, re platforms:
- netbsd: I expect there will be nonen this year, as there was
none last year and I discussed it with Jukka then (I had to failed to
update the list in build.html).  (Jukka, if you plan to resume building,
please let us know.)

- irix: Christian M said he will try building.  (If it doesn't work out,
no big deal.)

- sparc-solaris: I have not yet heard from Vladimir despite repeated pleas.
Nelson, we need to use the results on your sparc fleet ...

I believe the other semi-problematic builds are in process.

Since no big stoppers are arising, I'm still planning to shut down TL'12
updates in a few more days and start switching over to the pretest with
the new binaries, etc.  We'll see how it goes.

Thanks,
Karl